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1.
Bol. latinoam. Caribe plantas med. aromát ; 18(5): 480-491, sept. 2019. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1008273

RESUMO

In the present study, we investigated the antiproliferative activity of essential oil from leaves of Melissa officinalis L. grown in Southern Bosnia and Herzegovina. In vitro evaluation of antiproliferative activity of the M. officinalis essential oil was carried out on three human tumor cell lines: MCF-7, NCI-H460 and MOLT-4 by MTT assay. M. officinalis essential oil was characterized by high percentage of monoterpenes (77,5%), followed by the sesquiterpene fraction (14,5%) and aliphatic compounds (2,2%). The main constituents of the essential oil of M. officinalis are citral (47,2%), caryophyllene oxide (10,2%), citronellal (5,4%), geraniol (6,6%), geranyl acetate (4,1%) and ß- caryophyllene (3,8%). The essential oil showed significant antiproliferative activity against three cancer cell lines, MOLT-4, MCF-7, and NCI-H460 cells, with GI50 values of <5, 6±2 and 31±17 µg/mL, respectively. The results revealed that M. officinalis L. essential oil has a potential as anticancer therapeutic agent.


En el presente estudio, investigamos la actividad antiproliferativa del aceite esencial de las hojas de Melissa officinalis L. cultivadas en el sur de Bosnia y Herzegovina. La evaluación in vitro de la actividad antiproliferativa del aceite esencial de M. officinalis se llevó a cabo en tres líneas celulares de tumores humanos: MCF-7, NCI-H460 y MOLT-4 utilizando el ensayo de MTT. El aceite esencial de M. officinalis se caracterizó por un alto porcentaje de monoterpenos (77,5%), seguido de la fracción sesquiterpénica (14,5%) y compuestos alifáticos (2,2%). Los principales constituyentes del aceite esencial de M. officinalis fueron citral (47,2%), óxido de cariofileno (10,2%), citronelal (5,4%), geraniol (6,6%), acetato de geranilo (4, 1%), y ß-cariofileno (3,8%). El aceite esencial mostró una actividad antiproliferativa significativa contra las líneas celulares de cáncer MOLT-4, MCF-7 y NCI-H460, con valores GI50 de <5, 6±2 y 31±17 µg/mL, respectivamente. Los resultados revelaron que el aceite esencial de M. officinalis L. tiene potencial como agente terapéutico contra el cáncer.


Assuntos
Óleos Voláteis/farmacologia , Melissa , Antineoplásicos/farmacologia , Sesquiterpenos/análise , Técnicas In Vitro , Óleos Voláteis/química , Células Tumorais Cultivadas , Folhas de Planta , Monoterpenos/análise , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Antineoplásicos/química
2.
Bol. latinoam. Caribe plantas med. aromát ; 18(5): 492-503, sept. 2019. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1008286

RESUMO

The aim of the present work was to optimize the main experimental variables of a procedure using HS-SPME/GC-MS as the analytical methodology to establish the profile of the volatile compounds present in aerial parts of Hedeoma multiflorum Benth. The influence of the type of fiber, equilibrium time, extraction time and extraction temperature on the composition of the volatile compounds was determined using response surface methodology (RSM), and the parameters of the models were corroborated by multiple linear regressions. The results showed that the regression models generated adequately explained the data variation and represented the relationships between the parameters and their responses. The optimal analysis conditions from the contour plots were established (DVB/CAR/PDMS fiber, with a 10 min equilibrium time, 10 min extraction time, and 40°C). Under these conditions, 41 volatile components in the whole plant were determined, which represents more than those reported using hydrodistillation.


El objetivo del presente trabajo fue optimizar las principales variables experimentales de un procedimiento HS-SPME/GC para establecer el perfil de compuestos volátiles presentes en la parte aérea de Hedeoma multiflorum Benth. Se determinó la influencia de las variables tipo de fibra, tiempo de equilibrio, tiempo de extracción y temperatura de extracción sobre la composición de los volátiles, utilizando una met odología de superficie de respuesta (RSM) y los parámetros del modelo se corroboraron por regresión lineal múltiple. Los resultados demostraron que los modelos de regresión generados explican adecuadamente la variación de los datos y representaron significativamente las relaciones reales entre los parámetros y sus respuestas. Las condiciones óptimas de análisis fueron establecidas (DVB/CAR/PDMS, con un tiempo de equilibrio de 10 minutos, un tiempo de extracción de 10 minutos y trabajando a 40°C). Utilizando esta metodología, se determinaron 41 componentes volátiles en planta entera, más que los reportados mediante hidrodestilación.


Assuntos
Hedeoma , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/química , Cromatografia Gasosa-Espectrometria de Massas/métodos
3.
Shokuhin Eiseigaku Zasshi ; 60(4): 73-81, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31474654

RESUMO

Multilayer laminated films may contain organic solvents derived from adhesives, printing inks and so on. A headspace-GC/MS analysis method for the simultaneous determination of 30 substances such as toluene, xylene, acetone, methyl ethyl ketone, ethyl acetate, butyl acetate, methanol, ethanol, was developed. A N,N-dimethyl formamide solution containing an internal standard substance was added to the sample. After leaving overnight at room temperature, the headspace gas was analyzed by GC/MS. This method was applicable to a laminate film made of various materials. The organic solvents such as toluene, ethyl acetate, and heptane were detected from 6 out of 42 food packaging bags made from laminated film on Japanese market using this method.


Assuntos
Embalagem de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Solventes/análise
4.
An Acad Bras Cienc ; 91(3): e20180140, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31508662

RESUMO

Ackee (Blighia sapida K. D. Koenig) is an exotic fruit widely consumed in the Caribbean countries. While there is extensive research on the presence of hypoglycin A, other bioactive compounds have not been studied. We identified and quantified the changes in bioactive molecules (total phenol, ascorbic acid, hypoglycin A, squalene, D: A-Friedooleanan-7-ol, (7.alpha.), and oleic acid), antioxidant potential, and volatile compounds during two stages of ripe. A clear reduction in hypoglycin A, ascorbic acid, and total polyphenols during the maturation process were observed. On the contrary, oleic acid, squalene, and D: A-Friedooleanan-7-ol, (7.alpha.) contents increased about 12, 12, and 13 times, respectively with advancing maturity. These bioactive molecules were positively correlated with radical scavenging (DDPH and ABTS). Solid phase microextraction (SPME) and gas chromatography coupled mass spectrometry (GC/MS) analysis revealed more than 50 compounds with 3-penten-2-one and hexanal as the major compounds in the fully ripe stage. The results suggested that ripe ackee arilli could serve as an appreciable source of natural bioactive micro-constituents.


Assuntos
Antioxidantes/farmacologia , Blighia/química , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas , Hipoglicinas/química , Polifenóis/química , Esqualeno/química
5.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(9): 870-873, 2019 Sep 10.
Artigo em Chinês | MEDLINE | ID: mdl-31515778

RESUMO

OBJECTIVE: To assess the value of dry blood spot tandem mass spectrometry for the diagnosis of autism spectrum disorder (ASD). METHODS: Peripheral blood samples of 277 autistic children were collected. Their amino acid and carnitine profiles were detected by liquid chromatography tandem mass spectrometry. Urine samples of suspected patients were collected for verification by gas chromatography mass spectrometry. Blood samples were also taken for genetic testing. RESULTS: Of the 277 children with ASD, 19 (6.9%) were suspected to be with inborn error of metabolism (IEM), which included 6 cases with amino acidemia, 9 with organic acidemia and 4 with fatty acidemia. Three cases of phenylketonuria, one case of homocysteinemia, one case of propionemia, one case of methylmalonic acidemia, one case of glutaric acidemia, one case of isovaleric acidemia, one case of argininemia, one case of citrullinemia I and four cases of primary carnitine deficiency were confirmed by genetic testing, which yielded an overall diagnostic rate of 5.1% (14/277). CONCLUSION: Our result has provided further evidence for the co-occurrence of ASD and IEM. Tandem mass spectrometry has a great value for the diagnosis and treatment of ASD in childhood.


Assuntos
Transtorno do Espectro Autista/diagnóstico , Erros Inatos do Metabolismo/diagnóstico , Erros Inatos do Metabolismo dos Aminoácidos/complicações , Erros Inatos do Metabolismo dos Aminoácidos/diagnóstico , Transtorno do Espectro Autista/complicações , Criança , Teste em Amostras de Sangue Seco , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Erros Inatos do Metabolismo/complicações , Espectrometria de Massas em Tandem
6.
Medicine (Baltimore) ; 98(33): e16827, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31415401

RESUMO

INTRODUCTION: Ornithine transcarbamylase deficiency (OTCD) is a common metabolic disease of urea circulation disorder. We reported the clinical, brain imaging and genetic characteristics of 2 cases with OTCD. The patients' clinical features, novel gene mutations, cranial MR specific imaging changes and blood tandem mass spectrometry, and urine gas chromatography-mass spectrometry were, retrospectively, analyzed. PATIENT CONCERNS: Patient 1 was a 1.6-year-old female. She was admitted to the hospital with 2-months history of general irritability and disturbance of consciousness for a day. Patient 2 was a 3.7-year-old female. She was admitted to the hospital due to decline of language ability and irritability for 5 days. Blood tandem mass spectrometry and urine gas chromatography-mass spectrometry showed uracil and orotate increased significantly in urine while amino acids in the urea cycle ring were in the normal range. The features of brain MRI are consistent with those of urea circulatory disorders. Gene detection showed 1 novel mutation in the OTC gene (c.658C>T) in patient 1 and, 1 novel mutation (c.298+2T>G) in the OTC gene in patient 2. DIAGNOSIS: Combined with metabolic screening and gene detection, both patients were diagnosed with OTCD. INTERVENTIONS: The patients' condition improved after following a low protein diet and receiving treatments for decreasing blood ammonia, energy supplement, correcting acid-base imbalance, and other symptomatic treatments. OUTCOMES: After prompt symptomatic treatment, the consciousness and cognition of the children improved. Besides, liver function also improved significantly. CONCLUSIONS: For patients with neurological symptoms and unexplained increase in transaminase and ammonia, OTCD should be considered as a possible diagnosis. Brain MRI can help the diagnosis of genetic metabolic encephalopathy and reflect the level of brain injury. Metabolic screening and genetic detection are helpful to make a confirmed diagnosis.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Imagem por Ressonância Magnética , Doença da Deficiência de Ornitina Carbomoiltransferase/diagnóstico por imagem , Espectrometria de Massas em Tandem , Pré-Escolar , Feminino , Humanos , Lactente , Doença da Deficiência de Ornitina Carbomoiltransferase/genética
7.
Sud Med Ekspert ; 62(4): 37-41, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31407704

RESUMO

The purpose of this work is to study fenspiride for the purposes and tasks of chemical and toxicological research. The technique of chemical-toxicological study of fenspiride in urine by preliminary and confirming methods is proposed. The authors proposed a method of thin - layer chromatography in the solvent system of acetone - 25% ammonia solution (9:1) in a preliminary study of fenspiride. The Rf value of fenspiride is 0.80±0.02. The degree of extraction when used as an extractant mixture of chloroform-propanol (9:1) is 28.1±1.4% The conditions for identification of fenspiride by gas chromatography-mass spectrometry (fenspiride retention time 11.1±0.1 minutes), followed by quantitative determination of the analyte, are proposed as a confirming method. The conditions for qualitative (retention time of fenspiride 8.1±0.1 minutes) and quantitative determination of fenspiride by high-performance liquid chromatography are proposed.


Assuntos
Toxicologia Forense/métodos , Compostos de Espiro/química , Compostos de Espiro/toxicidade , Cromatografia em Camada Delgada , Cromatografia Gasosa-Espectrometria de Massas
9.
Sud Med Ekspert ; 62(4): 47-54, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31407706

RESUMO

The purpose of the work is to determine the optimal conditions for isolating amlodipine, to purify it by the method of column chromatography and to develop a method for detecting it in biological material. TLC, GC-MS, low pressure column chromatography, and HPLC were used for analysis. We studied the comparative isolation of amlodipine from biological material using 13 isolating agents of organic nature, water, and aqueous solutions. The use of acetone as an insulating agent for the extraction of amlodipine from tissues of cadaver organs has been substantiated. The possibility of purification of the analyzed compound from the endogenous substances of the biomaterial is shown by the method of reversed phase chromatography in a column of the Silasorp S-18 sorbent of 30 µm. A technique has been developed for detecting amlodipine in the tissues of cadaveric organs (liver), which corresponds to the necessary parameters of linearity, selectivity, accuracy, precision and stability. The limits of detection and quantification of amlodipine by the proposed method are 0.25·10-6 and 4.0·10-6 g, respectively, in 1 g of the biomaterial.


Assuntos
Acetona , Anlodipino/isolamento & purificação , Cadáver , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Reprodutibilidade dos Testes
10.
J Chem Ecol ; 45(8): 649-656, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31407197

RESUMO

Pheromone-baited traps can be excellent tools for sensitive detection of insects of conservation concern. Here, identification of the sex pheromone of Trichopteryx polycommata (Denis & Schiffermüller, 1775), an under-recorded UK priority species, is reported. In analyses of extracts of the pheromone glands of female T. polycommata by gas chromatography coupled to electroantennographic recording from the antenna of a male moth, a single active component was detected. This was identified as (Z,Z)-6,9-nonadecadiene (Z,Z6,9-19:H) by comparison of its mass spectrum and retention times with those of the synthetic standard. In a pilot field trial in Kent, UK, T. polycommata males were caught in pheromone traps baited with lures loaded with 1 mg and 2 mg (Z,Z)-6,9-19:H. Optimum lure loading was identified in a further five trials in Kent, Sussex and Lancashire where lures of 0, 0.001, 0.01, 0.1, 1, 2, 5 and 10 mg loadings were tested. Traps baited with 1 to 10 mg of ZZ6,9-19:H caught significantly more T. polycommata than traps baited with 0 mg and 0.001 mg. In a pilot survey of T. polycommata using pheromone lures around Morecambe Bay, UK, T. polycommata males were captured at 122 new sites within the three counties where trials took place, demonstrating the potential of pheromone monitoring to increase knowledge of abundance, distribution and ecology of this elusive species.


Assuntos
Mariposas/fisiologia , Atrativos Sexuais/química , Animais , Espécies em Perigo de Extinção , Ácidos Graxos Insaturados/química , Ácidos Graxos Insaturados/farmacologia , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Feromônios/química , Feromônios/farmacologia , Atrativos Sexuais/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos
11.
J Chem Ecol ; 45(8): 673-683, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31407198

RESUMO

Animals modulate intraspecific signal shape and intensity, notably during reproductive periods. Signal variability typically follows a seasonal scheme, traceable through the expression of visual, acoustic, chemical and behavioral patterns. The chemical channel is particularly important in lizards, as demonstrated by well-developed epidermal glands in the cloacal region that secrete lipids and proteins recognized by conspecifics. In males, the seasonal pattern of gland activity is underpinned by variation of circulating androgens. Changes in the composition of lipid secretions convey information about the signaler's quality (e.g., size, immunity). Presumably, individual identity is associated with a protein signature present in the femoral secretions, but this has been poorly investigated. For the first time, we assessed the seasonal variability of the protein signal in relation to plasma testosterone level (T), glandular activity and the concentration of provitamin D3 in the lipid fraction. We sampled 174 male common wall lizards (Podarcis muralis) over the entire activity season. An elevation of T was observed one to two months before the secretion peak of lipids during the mating season; such expected delay between hormonal fluctuation and maximal physiological response fits well with the assumption that provitamin D3 indicates individual quality. One-dimensional electrophoretic analysis of proteins showed that gel bands were preserved over the season with an invariant region; a result in agreement with the hypothesis that proteins are stable identity signals. However, the relative intensity of bands varied markedly, synchronously with that of lipid secretion pattern. These variations of protein secretion suggest additional roles of proteins, an issue that requires further studies.


Assuntos
Glândulas Exócrinas/metabolismo , Lipídeos/análise , Lagartos/fisiologia , Proteínas de Répteis/análise , Animais , Desidrocolesteróis/análise , Eletroforese em Gel de Campo Pulsado , Cromatografia Gasosa-Espectrometria de Massas , Metabolismo dos Lipídeos , Lipídeos/química , Masculino , Análise de Componente Principal , Estações do Ano , Comportamento Sexual Animal , Testosterona/sangue
12.
Ann Parasitol ; 652019.
Artigo em Inglês | MEDLINE | ID: mdl-31376245

RESUMO

In order to finding of potent natural medication/agent which can kill giardial cysts in the interval between lysing of outer membrane of cysts due to exposure by acidic condition of stomach and their encystation in proximal small intestine, In-vitro antigiardial activity and GC-MS analysis of Eucalyptus globulus and Zingiber officinalis against Giardia lamblia were studied in simulated condition to human's body singly and in combination. Essential oils were extracted and their chemical components were identified via GC-MS method. After purification, cysts were exposure to acidic condition and were challenged by different concentrations of essential oils in simulated condition to human's body. Percentages of inactivated (killed) cysts as efficacy of antigiardial activity were calculated and analyzed statistically. Presence of 1,8-eucalyptol, α-pinene, α-terpineol acetate, etc. in essential oil of E. globulus and presence of geraniol, α-zingiberene, (E,E)-α-farnesene, etc. in Z. officinalis essential oil were identified. Highest antigiardial activity (73.55%) was observed for eucalyptus essential oil in time 480 minutes after exposure. Efficacies of ginger and combined essential oils were different in different times. This study shows considerable antigiardial activity for both of essential oils singly and in combination together against giardial cysts. In-vivo study of protective effect of these essential oils against giardiasis can be considered as a subject for next studies.


Assuntos
Eucalyptus , Cromatografia Gasosa-Espectrometria de Massas , Giardia lamblia , Gengibre , Óleos Voláteis , Eucalyptus/química , Giardia lamblia/efeitos dos fármacos , Gengibre/química , Humanos , Óleos Voláteis/farmacologia
13.
Plant Dis ; 103(10): 2541-2547, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31432772

RESUMO

To prevent the spread of anthracnose in strawberry plants and characterize the metabolic changes occurring during plant-pathogen interactions, we developed a method for the early diagnosis of disease based on an analysis of the metabolome by gas chromatography-mass spectrometry. An examination of the metabolic profile revealed 189 and 202 total ion chromatogram peaks for the control and inoculated plants, respectively. A partial least squares discriminant analysis (PLS-DA) model was conducted for the reliable and accurate discrimination between healthy and diseased strawberry plants, even in the absence of disease symptoms (e.g., early stages of infection). ANOVA (analysis of variance) and orthogonal partial least squares analysis (OPLS) identified 20 metabolites as tentative biomarkers of Colletotrichum theobromicola infection (e.g., citric acid, d-xylose, erythrose, galactose, gallic acid, malic acid, methyl α-galactopyranoside, phosphate, and shikimic acid). At least some of these potential biomarkers may be applicable for the early diagnosis of anthracnose in strawberry plants. Moreover, these metabolites may be useful for characterizing pathogen infections and plant defense responses. This study confirms the utility of metabolomics research for developing diagnostic tools and clarifying the mechanism underlying plant-pathogen interactions. Furthermore, the data presented herein may be relevant for developing new methods for preventing anthracnose in strawberry seedlings cultivated under field conditions.


Assuntos
Biomarcadores , Colletotrichum , Fragaria , Cromatografia Gasosa-Espectrometria de Massas , Metabolômica , Biomarcadores/análise , Colletotrichum/fisiologia , Fragaria/microbiologia
14.
J Chem Ecol ; 45(8): 657-666, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31407199

RESUMO

The box tree moth, Cydalima perspectalis, is an invasive pest in Europe causing damage on Buxus species. In this study, we aimed to develop a "bisexual" lure to attract both female and male moths. Based on a previous screening bioassay we tested methyl salicylate, phenylacetaldehyde and eugenol as potential attractants in different combinations. The trapping results showed that both binary and ternary blends attracted male and female moths. Catches with these blends were comparable to catches with the synthetic pheromone. Subsequently we carried out single sensillum recordings, which proved the peripheral detection of the above-mentioned compounds on male and female antennae. To identify synergistic flower volatiles, which can be also attractive and can increase the trap capture, we collected flower headspace volatiles from 12 different flowering plant species. Several components of the floral scents evoked good responses from antennae of both females and males in gas chromatography-electroantennographic detection. The most active components were tentatively identified by gas chromatography coupled mass spectrometry as benzaldehyde, cis-ß-ocimene, (±)-linalool and phenethyl alcohol. These selected compounds in combination did not increase significantly the trap capture compared to the methyl salicylate- phenyacetaldehyde blend. Based on these results we discovered the first attractive blend, which was able to attract both adult male and female C. perspectalis in field conditions. These results will yield a good basis for the optimization and development of a practically usable bisexual lure against this invasive pest.


Assuntos
Comportamento Animal/efeitos dos fármacos , Mariposas/fisiologia , Feromônios/farmacologia , Animais , Eugenol/química , Eugenol/farmacologia , Feminino , Flores/química , Flores/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Controle de Insetos , Masculino , Monoterpenos/química , Monoterpenos/farmacologia , Feromônios/análise , Robinia/química , Robinia/metabolismo , Rosa/química , Rosa/metabolismo , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/farmacologia
15.
Waste Manag ; 96: 1-8, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31376953

RESUMO

Samples of sunflower Waste Cooking Oils (WCOs) subjected to several cycles of frying were treated with water under four different combinations of temperature and pH. Several aspects of the chemical composition of edible, non-treated and processed samples was determined by three different analytic techniques: headspace Solid-Phase Microextraction (HS-SPME) coupled with gas-chromatography (GC), 1H NMR spectroscopy and ESI-MS spectrometry. Thus, a characteristic chemical fingerprint of each sample was derived and proposed as useful set of tools for the optimization of recycling of WCOs. On the basis of the presented results, a mini-plant for the production of bio-lubricants and bio-solvents with a circular economy approach was designed and herein described.


Assuntos
Óleos Vegetais , Microextração em Fase Sólida , Culinária , Cromatografia Gasosa-Espectrometria de Massas , Reciclagem
16.
Food Chem ; 298: 125026, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260961

RESUMO

Roasted cotyledons of the Chilean hazelnut (Gevuina avellana) are appreciated as snacks. The aim of our work was to assess the fatty acid, oxylipin and phenolic composition using gas chromatography (GC) coupled to mass spectrometry (MS), ultra- high performance liquid chromatography (UHPLC) coupled to MS and HPLC coupled to diode array detector (HPLC-DAD). Additionally, various antioxidant activities were assessed. The inhibition of α-glucosidase, α-amylase, lipase, cyclooxygenases-1 and -2 (COX-1/COX-2), and lipoxygenase was determined. The main fatty acids were oleic and 7-hexadecenoic acids. Eight phytoprostanes and three phytofurans were identified and quantified. Hydroxybenzoic and hydroxycinnamic acids were the main phenolic compounds. Oils showed antioxidant activity determined by EPR, and inhibition of COX-1/COX-2. The statistical analysis showed that the roasting does not affect the composition of the samples. The occurrence of oxylipins in this species is reported for the first time. Chilean hazelnuts can be considered a source of health promoting compounds.


Assuntos
Antioxidantes/química , Corylus/química , Síndrome Metabólica/enzimologia , Oxilipinas/análise , Fenóis/análise , Chile , Ácidos Cumáricos/análise , Cromatografia Gasosa-Espectrometria de Massas , alfa-Amilases/antagonistas & inibidores , alfa-Glucosidases/metabolismo
17.
J Agric Food Chem ; 67(32): 9112-9120, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31314506

RESUMO

A reliable and robust tool for supporting the panel test in virgin olive oil classification is still required. We propose four chemometric approaches based on t test, principal component analysis (PCA) and linear discriminant analysis (LDA), applied for combining sensorial data, and chemical measurements. The former was from the panel test, and the latter was from headspace solid-phase microextraction-gas chromatography-mass spectrometry quantitation of 73 volatile organic compounds (VOCs) of 1223 typical commercial virgin olive oils, with most of them recognized as difficult to classify with accuracy by the panel test. The approaches were developed and validated, and the best results, with 83.5% correct classification, were using the PCA-LDA approach. Among the other methods, developed for proposing simplified procedures based on a smaller number of VOCs, the best method gave 80.1% correct classification only using 10 VOCs. All of the approaches suggested that octane, heptanal, pent-1-en-3-ol, Z-3-hexenal, nonanal, and 4-ethylphenol should be considered as a basis of volatiles for classification of olive oil samples.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Azeite de Oliva/química , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/isolamento & purificação , Análise Discriminante , Humanos , Olea/química , Azeite de Oliva/classificação , Análise de Componente Principal , Paladar
18.
Bioresour Technol ; 291: 121822, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31352163

RESUMO

Catalytic fast pyrolysis of soda lignin was examined at different temperatures (500,600,700,800 and 900 °C) in the presence of three zeolites with different Si/Al ratio using the Py-GC/MS in order to investigate best catalytic system. The three zeolites are y-zeolite (8-9), mordenite (15-17), ZSM-5 (30-40), which have static pore sizes 0.74, 0.65, and 0.59 nm respectively. The shape and acidity of zeolites, as well as pyrolysis temperature, have a significant effect on product distribution in catalytic fast pyrolysis. Y-zeolite was the most effective catalytic system among all catalysts for deomethoxylation and dehydroxylation of small oxygenates as well as bulky oxygenates to produce aromatics. However, mordenite and ZSM-5 could not convert the large oxygenates due to size exclusion and pore blockage. Highest yield of aromatics with significant amount of aromatic dimers was obtained over y-zeolite and then yield of aromatics followed in order by mordenite and ZSM-5 at 800 °C.


Assuntos
Lignina/química , Zeolitas/química , Catálise , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta , Pirólise
19.
Bioresour Technol ; 291: 121802, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31352164

RESUMO

In this study, the potential of the pyrolysis method to overcome the negative effects of Azolla-filiculoides in infected areas was thoroughly investigated. Non-catalytic pyrolysis experiments were conducted at a temperature range of 400-700 °C. The highest possible bio-oil yield (35 wt%) was attained at 500 °C. To achieve the best chemical composition of bio-oil and higher amount of synthesis gas the catalytic pyrolysis were conducted in a dual-bed quartz reactor at the optimum temperature (500 °C). Although, all three catalysts (pyro-char, modified pyro-char (MPC), and Mg-Ni-Mo/MPC) showed almost an impressive performance in promotion of the common reactions, Mg-Ni-Mo/MPC catalyst have illustrated the stunning results by increasing the percentage of furan compounds from 5.25% to 33.07%, and decreasing the acid compounds from 25.56% to 9.09%. Using GC-MS and GC-FID liquid and gaseous products were fully analyzed. The carbon-based catalysts were also evaluated via FTIR, FESEM, EDX, and BET analyses.


Assuntos
Polifenóis/biossíntese , Traqueófitas/metabolismo , Biocatálise , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta , Óleos Vegetais , Pirólise
20.
J Chem Ecol ; 45(7): 579-587, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31256322

RESUMO

Domestic cats (Felis silvestris catus) are solitary and territorial, and mark their territories by spraying urine, which emits a strong odor produced by volatile organic compounds (VOCs). Previous studies have focused on identifications of specific VOCs, such as 3-mercpto-3-methyl-1-butanol, a cat-specific VOCs. However, little is known about how whole volatile profiles of their sprayed urine change over time or how the profiles differ among individuals. This study investigated temporal changes and individual differences of volatile profiles produced by whole VOCs in cat urine, and the ability of cats to discriminate between these scent differences. Volatile profiles of fresh and aged cat urine were analyzed by using two-dimensional gas chromatography-mass spectrometry with a VOC preconcentrator comprehensively. Volatile profiles produced by hundreds of VOCs emitted from cat urine were influenced primarily by the age of the urine, and secondarily by individuality. During habituation-dishabituation tests, subjects discriminated between fresh and 24 h-old samples of same individuals, and between odor of different individuals from 0 h-, 3 h-old, and 24 h-old samples. These results strongly suggest that cats can recognize conspecific individuals via olfaction. Since most VOCs varied among individuals but were not stable over time, their urine may contain unknown VOCs that vary among individuals, are stable over time, and act as individual recognition signals.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos Orgânicos Voláteis/urina , Animais , Comportamento Animal , Gatos , Análise Discriminante , Masculino , Análise de Componente Principal , Fatores de Tempo , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/isolamento & purificação
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